"I
was born at Bordeaux April 16th, 1728. My father was a merchant settled
there, but born in Ireland and the son of a citizen of Belfast of
Scottish
extraction. My father's residence at Bordeaux was in the suburb
called
the Chartron, and he had also a farm and country house and vineyard on
the other side of the river on a hill called Lormont which commands a
fine
prospect of the river and city." 1

Education.
Joseph Black's mother taught all of her children (8 sons and 5
daughters)
to read English. Black left home at age 12 to study Latin and
Greek
in Belfast where he lived with relatives. Black was educated in
medicine
at Glasgow University. Around 1750 he moved to Edinburgh, and in
June 1754 presented his inaugural dissertation, On the Acid
Humour
Arising from Food and Magnesia alba.2
The thesis dealt principally with value of magnesia as an antacid.

Professor
Black. Joseph Black began academic
life
at age 28 as professor of anatomy and lecturer of chemistry 1756.
Black spent most of his professional life as professor of chemistry in
Edinburgh from 1766 - 1799. In Black's time, chemistry was
regarded as
a subordinate of medicine — its sole purpose was to
provide remedies for
treatment of disease. Black was a very popular lecturer —
attracting
audiences of several hundred students, often performing lecture
experiments.

"Many
were induced, by the report of his students, to attend his courses,
without
having any particular relish for chemical knowledge."3

Black's lecture demonstrations included several that chemistry teachers
still do to this day — including pouring 'fixed air' over a candle from
a jar, and exhaling through a tube into limewater. Late in
Black's
life, Lavoisier presented his oxygen theory, which Black quickly
accepted
and taught to his students rather than the traditional phlogiston
theory.

Black died on November 10, 1799 peacefully seated in his chair at the
University of Edinburgh.

Fixed
Air. Black showed that magnesia
alba
(now xMgCO3, yMg(OH)2,
zH2O), when heated gave
off water
plus 'fixed air' (now CO2)
—
an 'air' previously described by van Helmont as gas sylvestre.
The
residue, calcined magnesia (now MgO), was lighter and more
alkaline.
Limestone (now CaCO3) did
the
same, but Black was able to study this sequence quantitatively:

limestone
+ heat yields fixed air + quicklime

[now:
CaCO3(s)
CO2(g) + CaO(s)]

quicklime
slaked with water and then boiled with mild alkali(now
K2CO3),the
alkali becomes caustic and original weight of limestone restored

[now:
CaO(s) + H2O(l)
Ca(OH)2(s, aq)

Ca(OH)2(s,
aq) + K2CO3
CaCO3(s) + 2 KOH(aq)]

"If
quicklime is mixed with a dissolved alkali it shows an attraction for
fixed
air superior to that of the alkali. It robs this salt of its air
and thereby becomes mild itself...."3

Lasting
accomplishments.

•
Black
established for the first time that a gas could combine with a solid,
previously
believed to be impossible.

• Black
recognized
that there were various types of airs (air had been considered an
element.)
'Fixed air' was a definite chemical entity different from air.
This
completely changed the understanding of the chemical nature of gases
and
ushered in the era of pneumatic chemistry.

• Black
is considered
the 'founder of calorimetry.' His pioneering work with latent
heats
of fusion and evaporation and with what is now call specific heat and
heat
capacity proved invaluable to James Watt who used the information to
improve
the steam engine. (In Black's time, heat was considered a kind of
matter.)

• Perhaps
Black's
most important contribution even escaped his own knowing. Black
explained
his observations without reference to the phlogiston theory. This
impressed Lavoisier and provided him with an important clue as he
formulated
his oxygen theory.

References.

1 from autobiographical memorandum, The Life
and
Letters of Joseph Black, by Sir William Ramsay, Constable,
(1918)

2 translation from Latin appears in J Chem Ed
(1935), xii, 225, 268

3 from the only biography of Black, written by his
successor
Robison and printed in A Short History of Chemistry, J.
R.
Partington, 3rd edition, (1957)